Automatic throttle stop



C. F. TAYLOR AUTOMATIC THROTTLE STOP Feb. 28, 1928.

Filed Aug.-1, 1921 2 Sheets-Sheet 1 Feb. 28, 1928. 1,660,731 c}. F. TAYLOR AUTOMATIC THRDTTLE STOP Filed Aug.1, 1921 2 Sheets-Sheet 2 Patented as. 2a, was.

r EEC CHARLES F TAYLOR, OF DAYTON, OHIO.

AUTOMATIC THROTTLE STOP.

Application filed August 1, 1921. Serial no. 488,999.

This invention relates to an automatic throttle" stop and is particularly adapted-to be used in connection with the internal com bustion engines of aircraft.

Accordingto my invention a device responsive to differences in atmospheric pressure, such as a sylphon, is utilized to vary the position of a stop device in accordance with the atmospheric pressure at the altitude at which the aircraft is flying. The stop device is provided with a series of stepped surfaces which are adapted to be placed in alignment with a rod connected to the throt-. tle shaft of the engine so as to limit the movements of the throttle valve in accordance with the position of the particular surface thus presented to the rod. The various parts of the mechanism are arranged so that I the motion of the throttle is restricted without imposing any strain on the sylphon.

The nature of the invention will become apparent on reference to the following specification which describes the invention in connection with the accompanying drawings. In the drawings, similar reference characters designate corresponding parts throughout the several views, which may be identified as follows: V

Figure 1 is a central vertical section through the casing of the mechanism;

Figure 2 is a detail perspective viewof the plunger, stepped block and rivets in dis assembled relation; j I

Figure 3 is a sectional view on the'line 33 of Figure 1; and 2 Figure sis acentral vertical modified form of the invention.

The numeral 10 designates a hollow, rigid casing which is preferably of cylindrical form and provided with abott'om flange 11, which is secured to a base platex12 by means of suitablefastening devices 13. A sylphon let is attached at its lower end to the base plate 12 by means of rivets l5, and the upper end of the sylphon is closed by means of a sheet metal cap 16 which is bent inwardly so as to form the central depression 17. The sylphon .is preferably filled with dry air under desired 7 pressure .and hermetically sealed. The top of the casing is elongated at 18 and this portion is bored or otherwise suitably formed to provide a cylindrical chamber 18' in which a plunger 19 is adapted to reciprocate. The plunger is formed with a lower flange 20 provided'with apertures 21 section of a for receiving rivets 22 which secure the flange to the sheet metal cap 16 at the central 1 depression 17- The plunger 19 is longitudinally slotted at'its upper end as indicated at 23 and a case hardened steel block24 is'insorted in the slot 23 and retained therein by means of rivets 25 which .pass through aligning apertures formed through the bifurcated portions of the plunger and the block 24, re-

vpectively. The block 24:, as illustrated,

has substantially the section of'a right triangle andthe hypotenuse or lower .side in a this caseis providedwith a series of stepped surfaces, herein given the general designation 26 but designated successively in Figure Adjacent the elongated portion: or boss of the casing an offset portion 27 is provided,

and this offset portion'is formed with a lat-1 eral opening which intersects the cylindrical chamber '18 at'a point-within the rangeof the entire movement ofthe stepped-block.

A hardened steel rod 28 is inserted through i the lateral opening'of the offset portion and this rod is pivotally connected with a link 29, WlllCh in turn is pivotally connected to an arm 30 secured to'shaft 31 of the throttle valve by means'of a tapered pin 32 The connection between the rod28ian'd link 29 is preferably of the type which will permit longitudinal adjustment and for this-purpose acoupling 33 is used, having a threaded socket, for engaging the threads 34formed on the outer end of the rod 28. The coup ling 33 is formed with a suitable aperture 7 andis adapted to engage in the bifurcated I end of the link 29 and is thereto by apivot' pin 3 use with engines which are intended forf'ull pivotally connected throttle operation at high altitudes only, and

which must not be operated at full power belowa certain specified altitude. WVhen the engine is at sea level the normal position of the upper end 16 of the sylphon is shown by y the dottedlines in Figure 1. This-brings the plunger 19 and thestepped block into such position that the topmoststep 1 of the block is placed opposite the lateral opening in which the rod 28 operates, thereby limiting the inward travel of the'rod to a point which is practically flushwith the side walls of the cylinder 18 as indicatedby the numeral 36 As the airplane ascends to in Figure 1. higher altitudes, the decreased-atmospheric pressure is transmitted to the interior of the casing through the vents 37-Whi0h pierce i pressure 1 7 tion of the plunger is communicated to the ill the sidewalls thereof. This reduction of within the casing allows the air in the sylphon to expand and gradually increase the length of thesylphon andthereby-move the plunger 19 upwardly. This aestepped block and, as the steps ofthe block are positioned successively opposite the rod -28,the latter is a increased travel and when the altitude is reached at which the engine may be operated with the throttle wide open, the block 24 is entirely out of thepath of the rod '28 whereby the latteris granted a free move ment and may moveto the other side of the cylindrical portion 18; In this last position of the'block 2 the engine throttle maybe opened as wide as desired The sylphon l4 and the block 2- may be so designed as tolimit the travel of the throttle below any specified altitude; depending, of

course upon the size andlstiti'ness of the,

sylphon and the l'ieight-and number of steps in the block, and it will be understood that these arrangements can be varied to suit any type of engine. It is desired to call particular attention to the fact that the restriction of the moti'on of the throttle by the stepped block does not impose any strain. on the syliphon'or the connectionbetween the sylphon and the plunger as the impact is taken up by the, sidewalls of the cylindrical chamber 18'. In order to provide freedom of movement for the plunger '19, the top of the cy-' lindricalchamber is preferably formed with avent- 38 which permits air to escape from the chamber during the upward movement of the plunger.

I vents l-1 and encloses in d by the sylphon l3.

has sliding engagen'ient with t I Figure t illustrates a modified form of my invention in which a casing 40 provided with a sylphon 43. This casing is also formed with a longitudinal chamber 44 in which a plunger 45, secured to the sylphon's ll, isadaptcdto-reciprocate. The plunger 45 has" a transverse bore 1G which provides a clearance for a rod 47.

The lOClt-T is connected to the throttle valve of the enginoby means of a links-8. The top ot the casing 410 is forn'iedwith an enlarged transverse chamber 419 placed substanti-allyat right angles to t he chamber 44:. A lug or block projecting from the rod 47 he chamber alt) and is provided, with stepped surfaces adapted to engage against the adjacent side of the plunger 45 in accordance with the position of said plunger as deter- The rod 17 i is provided with an extension which is guided in lateral opening in the top ofthe casingformed on the side of the chamber 4:4. opposite-from the chamber 4C9.

The operation of this modified form of my invention is similar to that described above in econnection with the embodiment thereof allowed a con-espondingly' walls of the parting from the spirit and: scope of the in- .vention as defined inthe appended claims;

I claim l r 1. In a device of the class described, the:

combination with the throttle valve of an internal combustion engine, anddevices connected'to the throttle valve and movable therewith, of a block adjustable; in position "adapted to coact with said devices for limiting the extent of the opening movements of said valve, and mechanism responsive to changes in atmospheric pressure for adjusting the position of said block.

2. The combination with the of an internal combustion engine of an airthrottle valve craft and a rod connected to the throttle valve and movable therewith, of ahca'sing having a chamber formed therein, a plunger adapted to reciprocate in said chamber a device responsive to changes in atmospheric pressure for actuating said plunger, and a stop block connected to said plunger for limiting the movement of said rod in one d1- 'rection, whereby impact between said. rod and block 18 communicated by the plunger to; v the walls of said chamber withoutimposing undue strain on said device. I,

3. In combination with the throttle valve of an internal combustion engine a pressure responsive device, an element operatively connected to the throttle valve, an element operatively connected to the; pressure respon sive element, one of saidelements having stepped surfaces engageable' ;W1i1l1 the other elen'ient tor limiting the movement of the throttle valve in accordance with the atmos'-.

phericpressure,- l'. Thecombination 1th the throttle valve of an internal combustionengine-ofan air-- craft, and devlces connected to the, throttle,

valve and movable therewith, of acasing having vents communicating with the "a tmosphere and a cl'iamberj formed therein, barometr c means within said casing, and a plungcii connected to. said means and adapted to reciprocate in said chamber in accordance with-the movements of said means,

said devices including stepped surfaces adaptedto coact with said plunger for limiting the movement of the throttle valve to various extents depending upon the altitude V of theaircraft;

no i

In testimonyvw-hereof l have aiiixed my i signature; 1 i i CHARLES E; TAYLOR, 

